Lathe hand gauge



Aug.`2, 1938. ,J. MELuzlN LATHE HAND GAUGE Filed sept. 2, 1957 Patented' Aug. 2, 1938 PATENT o-Frics j LA-THEj GAUGEI J ulius'Meluzin, Washington, li). C. i npplieacionfiseptember 2, 19-37; seriar No. mazda 2 Claims;

This' inventi'on' relates to tool' setting gauges and has special' reference to' a lathe hand gau'ge for setting a lathe tool accurately in proper position to effect the cutting of a work piece or blank' V mounted in a lathe for turning to desired size' and shape'.

One important object of the' invention is'to'p'rovide a novel gau'ge Which may' be readi'ly and conveniently applied to the deadcenter' spindle of any lathe wherein the diameter`v of the spindle is within the limits of gripping adjustment of the gange;

A second important object of the invention is to provide a novel gauge'for u'seon the dead cen'- V ter' spindl'e of a lathe' and' which, when applied to such a` spin'dle, may be readily set to' bring a gauge surface into suchl position that a' tool having its point set to engage or` be fiush' with' such surface Will be in correct position for cutting the 202 work. `4

A third important object of the invention l's to provide .a gauge` of the foregoing character acljustable-` for' use in' setting bothI turning and boring lathe' tools. A fourth important object of the' invention is to providea'novel'gauge of this character having means' Whereby a thread cutting lathe tool`` may be accurately set to proper cutting position.

With the' above and other objects in view' as wi1l-`be` hereinafter apparvent, theinvention consists ingeneral of certain novell details of construction` and combinations off parts hereihafter fully described, illustrated in the accompanyng drawing and specifically'claimed'.

In the' .accompanying drawing lile characters`Y of reference indicate like parts in the several views, and:

Figure 1 is a side elevation of the novel gauge.

Figure 2 is a front edge view thereof.

Figure 3 is an enlarged detail section on the line 3--3 of Figure 2.

Figure 4 is a plan view of a gauge element adjustable to the gange frame for use in setting a thread cutting lathe tool. v

Figure 5 is a section on the line 5-5 of Figure 1.

Figure 6 is a fragmentary front elevation showing a portion of a lathe with the novel gauge in position thereon.

In the embodiment of the invention as here illustrated there is provided a frame IO of substantially C-shape. or front portion I I, a rear portion |2 and an arouate portion I3 connecting said front and rear por- 55 tions. The major part of the frame is preferably This frame comprises a head i of I-shape in cross-section to economize in' weight without `sacrificing the essential strength and rigidity. Also the web of the I-shaped portion of the frame is provided with Weight relieving openings M.

v TheV head' l'l is formed with a front face or edge l'5`from which extend rearwardly the top face or edge' IG and the bottom face or edge il. The;` faces l`6 and l'l4 are at right angl'es to the face l'yand are consequently parallel. `The rear edge of the head H is formed by a pair of flat forwardly converging faces l8- which merge at their forward ends into a short flat face I!! parallel' to the face 15; The portion 26 of the head between the faces'` l'5 and l`9 is rectangular in cross-section so that it forms a species of boss for (purposes presently to be explained.

The'rear frame portion I'2 is also of rectangular cross-section to form a boss opposed to the boss 2-0; Through this rear frame portion extends a threaded bore* 21` having its axis aligned With the lineat which the two plane faces would intersect if lthey were continued until they met.

Cooperating with the faces [8 is an adjustable clamp device comprising a screw 22V` threaded into the bore 21 and rotatable by means of a knurled head 23 fixed on its rear end. A clamp head 25.1, is swivelled: on the front end of the screw 22 and has its forward face formed by a pair of flat rearwardly converging faces 25'merging at their adjarcent ends into a flat face 26. The faces 25' converg'e at equal angles to the axis of the screw 22 as do the faces IB.

In the' face l`5 is formed' a shallow transvers'e groove having' top and bottom edges 21 parallel to the face l'l and thus to each' other. This'groove also has a bottom face 28 parallel to the face l5. The edges 21 are disposed respectively above and below the axis of the screw 22 and at equal distances therefrom. A bore 29 extends rear- Wardly from the face l8 and is axially aligned with the screw 22 so that the faces IB converge to a common point on the axis of the bore. Extending laterally from one side of the head l l in axial intersecting relation with the bore 29 is a threaded bore 30 wherein is screwed a set screw 3l having a frusto-conical point and a knurled head 32. i

A variety of gauge points may be provided for use in connection with the frame although but two such points are shown herein. All of the points to be used in this gauge have certain features in common. Thus each point has a shank 33 and a head 34. Each shank is of proper size to fit closely in the bore 29 and is provided with a groove 35 wherein closely fits the point of the screw 3! when the gange point is positioned for use. Also the groove 35 is at such distance from the head 34 that the rear face 36 will fit against the groove bottom 28. The head 34 is provided with flat upper and lower faces 31 spaced to fit closely between the edges 21 upon the stem 33 being inserted in the bore or socket 29 and the head is provided with a flat horizontal gauge face 38 parallel to the face H and the axial line of the shank 33 lies in this face so that the planes of the faces I8 and 38 all meet at a common line of intersection. In the form of gange point4 shown in Figure 4 the face 38 is provided with a V-shaped notch 39 to receive the usual blnntly V-shaped point of a lathe thread cutting tool when setting the latter.

On thel face IB is mounted a sensitive spirit level 40 so arranged that the bubble thereof will be in central position upon the face ll being truly horizontal.

In use the appropriate gange point is assembled in the frame, facing either up or down as may be desired. The gange is then fitted on the dead center spindle l and the screw 22 rotated to clamp the spindle lightly between the faces l8 and 25. The gange is now rotatedvon the spindle until, if the bed of the lathe be transversely horizontal, the bubble of the gauge is centered whereupon the screw 22 is tightened to fix the gange in this position. The lathe carriage is now brought into such position that the tool 42 may have its point brought into contact with or flush with the point gange face 38 which thus positions the tool so that its point will lie in the horizontal plane of the axis of the work piece or blank 43 and the tool will thus be in the most eifective position for cutting the metal of the piece 43'.

The gange may be used to determine if the lathe bed is truly horizontal by resting the face H on the lathe bed to have the gauge extendtransversely thereof. If notl horizontal the bubble of the spirit level will move to a definite extent depending on the inclination of the bed from the horizontal. In setting the gauge the extent of deviation of the bubble must be observed and the same deviation obtained upon the gange being clamped in the spindle. This is necessary since the point of the tool for the mostV eifective cutting should lie in a plane defined in position by the axis of the lathe and the line of cross-feed of the tool.

If found convenient or desirable the gange may be applied to the work itself rather than the dead center spindle.

There has thus been provided a simple and efficient device ofthe ln'nd described and for the purpose specified.

It is obvious that minor changes may be made in the form and construction of the invention without departing from the material spirit thereof. It is not, therefore, desired to confine the invention to the exact form herein shown and described, but it is desired to include all such as properly come within the scope claimed.

I-Iaving thus described the invention, what is claimed as new, is:

1. In a gange for the purpose described, a substantially C-shaped frame including a pair of spaced terminal portions, one of said terminal portions constituting a head having a rear edge formed by a pair of flat forwardly converging faces, the other terminal portion having a screw threaded axially aligned Opening bisecting the angle between said faces, an adjustable clamping device comprising a screw threaded into said Opening and having a clamp head swivelled on its front end, said head having an Opening therein aligned with the threaded Opening, a gange point having a shank fitting revolubly in the Opening in said head and having a head provided with a plane gange face positioned diametrically of the shank, and a set screw extending laterally in said head and engaging said shank to hold the gange point with its gange face in adjusted position. i

2. In a gange for the purpose described, a substantially C-shaped frame including a pair of spaced terminal portions, one of said terminal portions constituting a head having a rear edge formed by a pair of flat forwardly converging faces, the other terminal portion having a screw threaded axially aligned opening bisecting the angle between said faces, an adjustable clamping device comprising a screw threaded into said Opening and having a clamp head swivelled on its front end, said head having an Opening therein aligned With the threaded Opening, a gange point having a shank fitting revolubly in the Opening in said head and having a head provided with a plane gange face positioned diametrically of the shank, and a set screw extending laterally in said head and engaging said shank to hold the gange point with its gange face in adjusted position, said shank having a circumferential groove and the set screw having a point fittting in said groove whereby the set screw may be partially unscrewed for rotation of the gange point while holding the shank from withdrawal from the Opening in the head.

JULIUS MELUZIN. 

